Authors:

The opto-electronic properties of carbon nanotubes depend
sensitively on their environment. Double-walled carbon nanotubes
(DWCNTs) offer an ideal configuration in which to study
interlayer electron-phonon coupling effects. Dispersed
sub-populations (MM, MS, SM, SS where M is metal and S is
semiconducting) of individualized DWCNTs were prepared in a three
part process consisting of purification to remove catalysts,
density gradient ultracentrifugation to remove dispersed SWCNT
and MWNT nanotubes, followed by additional ultracentrifugation of
purified DWCNT dispersions to separate the sub-species by
buoyancy. Extracted fractions were concentrated and dialyzed for
measurement. We perform resonance Raman spectroscopy (RRS) of
DWCNTs using a wide range of laser excitation wavelengths, from
NIR through UV, for vibrational modes including the
radialbreathing mode (RBM) and higher order graphite modes. In
order to measure the effects of electron-phonon coupling, we will
compare the Raman spectra for specific chirality nanotubes in a
double-walled complex with the behavior of individual SWCNTs of
the same chirality.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2010.MAR.K1.208